Utilization Of SRS For RPD Calibration In Wireless Communications

ABSTRACT

Various solutions with respect to relative phase discontinuity (RPD) calibration in wireless communications are described. A user equipment (UE) receives a single trigger signal from a network node of a wireless network. The UE then transmits a plurality of reference signals in sequence to the network node responsive to receiving the single trigger signal. The network node can perform RPD calibration based on relative phase difference between adjacent reference signals in time domain of the plurality of reference signals received from the UE.

CROSS REFERENCE TO RELATED PATENT APPLICATION(S)

The present disclosure is part of a non-provisional application claiming the priority benefit of U.S. Patent Application No. 62/557,194, filed on 12 Sep. 2017, the content of which is incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure is generally related to wireless communications and, more particularly, to relative phase discontinuity (RPD) calibration in wireless communications.

BACKGROUND

Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section.

Phase discontinuity refers to the change in phase between signals transmitted in any two adjacent timeslots. With or without a user equipment (UE) reporting the composition of its coherence group, it is desirable for a base station of a network in wireless communication with the UE to be able to assess the RPD situation at the UE.

SUMMARY

The following summary is illustrative only and is not intended to be limiting in any way. That is, the following summary is provided to introduce concepts, highlights, benefits and advantages of the novel and non-obvious techniques described herein. Select implementations are further described below in the detailed description. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter.

An objective of the present disclosure is to propose solutions, schemes, methods and apparatus that enable RPD calibration in wireless communications. It is believed that the proposed solutions, schemes, methods and apparatus would boost channel reliability and robustness as well as improve data throughput via UL multiple-input-and-multiple-output (MIMO).

In one aspect, a method may involve a processor of a user equipment (UE) receiving a single trigger signal from a network node of a wireless network. The method may also involve the processor transmitting a plurality of reference signals at different power levels in sequence to the network node responsive to receiving the single trigger signal.

In one aspect, an apparatus may include a transceiver and a processor coupled to the transceiver. The transceiver may be capable of wirelessly communicating with a network node of a wireless network. The processor may be capable of: (a) receiving, via the transceiver, signaling from the network node; (b) configuring, based on the signaling, one or more parameters with respect to transmission of a plurality of reference signals in sequence; (c) receiving, via the transceiver, a single trigger signal from the network node; and (d) transmitting, via the transceiver, the plurality of reference signals in sequence to the network node responsive to receiving the single trigger signal.

It is noteworthy that, although description provided herein may be in the context of certain radio access technologies, networks and network topologies such as 5^(th) Generation (5G) or New Radio (NR) mobile communications, the proposed concepts, schemes and any variation(s)/derivative(s) thereof may be implemented in, for and by other types of radio access technologies, networks and network topologies wherever applicable such as, for example and without limitation, Long-Term Evolution (LTE), LTE-Advanced, LTE-Advanced Pro, Internet-of-Things (loT) and Narrow Band Internet of Things (NB-IoT). Thus, the scope of the present disclosure is not limited to the examples described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of the present disclosure. The drawings illustrate implementations of the disclosure and, together with the description, serve to explain the principles of the disclosure. It is appreciable that the drawings are not necessarily in scale as some components may be shown to be out of proportion than the size in actual implementation in order to clearly illustrate the concept of the present disclosure.

FIG. 1 is a diagram of an example scenario in accordance with implementations of the present disclosure.

FIG. 2 is a diagram of an example scenario in accordance with implementations of the present disclosure.

FIG. 3 is a diagram of an example wireless communication environment in accordance with an implementation of the present disclosure.

FIG. 4 is a flowchart of an example process in accordance with an implementation of the present disclosure.

FIG. 5 is a flowchart of an example process in accordance with an implementation of the present disclosure.

DETAILED DESCRIPTION OF PREFERRED IMPLEMENTATIONS

Detailed embodiments and implementations of the claimed subject matters are disclosed herein. However, it shall be understood that the disclosed embodiments and implementations are merely illustrative of the claimed subject matters which may be embodied in various forms. The present disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments and implementations set forth herein. Rather, these exemplary embodiments and implementations are provided so that description of the present disclosure is thorough and complete and will fully convey the scope of the present disclosure to those skilled in the art. In the description below, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments and implementations.

Overview

Implementations in accordance with the present disclosure relate to various techniques, methods, schemes and/or solutions pertaining to uplink partial sub-frame transmission with respect to user equipment and network apparatus in wireless communications. According to the present disclosure, a number of possible solutions may be implemented separately or jointly. That is, although these possible solutions may be described below separately, two or more of these possible solutions may be implemented in one combination or another.

In 5G/NR mobile communications, a sounding reference signal (SRS) is a reference signal transmitted by a user equipment (UE) to a network node (e.g., gNB or eNodeB) of a mobile network. Based on the SRS, the network node can estimate channel quality in the uplink direction over one or more frequency bands. The network node can also perform frequency selective scheduling based on the SRS. Moreover, the network node can use SRS for uplink timing estimation as part of a timing alignment procedure.

Under a proposed scheme in accordance with the present disclosure, a UE may transmit SRS at different transmit power levels, which can be predefined, to a network node such as a base station (e.g., gNB, eNodeB or transmit-and-receive-point (TRP)) to aid mitigation of the RPD issue. Under the proposed scheme, the network node may trigger the UE to transmit SRS from transmitter (Tx) chains of the UE at different transmit power levels. Upon receiving the SRS transmitted by the UE at different transmit power levels, the network node may compare and log (or store) relative phase difference between transmissions of the SRS at different transmit power levels. Accordingly, the network node may be able to predict relative phase jump (discontinuity) that may occur when different transmit power levels are used by the UE in transmission for SRS and physical uplink shared channel (PUSCH). Moreover, the network node may be able to proactively compensate for relative phase jump or RPD.

For instance, with a two Tx chains at a UE, assuming that a network node is aware that there is α degrees (e.g., 180°) relative phase jump between SRS transmissions by the UE at 10 dBm and 20 dBm, and assuming a derived optimal precoder is [11]^(T) when the UE transmits SRS at 10 dBm, then when the UE transmits at 20 dBm for PUSCH the network node may indicate [1e^(−jαl180-π)1] instead of [11] to be used by the UE.

FIG. 1 illustrates an example scenario 100 in accordance with implementations of the present disclosure. Scenario 100 may involve a UE 110, a network node 120 (e.g., gNB or TRP) and a wireless network 130 (e.g., 5G/NR mobile network) of which network node 120 is a part. Under the proposed scheme, UE 110 may receive a single trigger signal from network node 120. In response to receiving the single trigger signal, UE 110 may transmit a plurality of reference signals (e.g., SRS) in sequence to network node 120.

In scenario 100, UE 110 may transmit the plurality of reference signals at different transmit power levels according to a power ramp schedule (e.g., increasing transmission power from P₁ to P₂ to P₃ in three sequential transmissions as shown in FIG. 1). Alternatively, UE 110 may transmit the plurality of reference signals at a predefined power level (not shown) for each. Additionally, UE 110 may transmit the plurality of reference signals at different time intervals, which can be evenly spaced (e.g., at time points T₁, T₂ and T₃ which are evenly spaced apart as shown in FIG. 1). Moreover, UE 110 may transmit the plurality of reference signals as evenly-spaced orthogonal frequency-division multiplexing (OFDM) symbols in a time domain.

Under a proposed scheme in accordance with the present disclosure, an RPD calibration procedure may be conducted with periodic or aperiodic SRS transmissions by the UE. Under the proposed scheme, with periodic SRS transmissions, the UE may transmit evenly-spaced SRS at different power levels. For instance, the UE may transmit evenly-spaced SRS according to a periodic power ramping schedule such as, for example and without limitation, 13 dBm, 18 dBm, 23 dBm, 13 dBm, and so on.

In an event that channel variation between two SRS transmissions at different power levels is small, the RPD calibration procedure may be based on the network node providing multiple triggers of aperiodic SRS transmissions by the UE, so long as the network node is able to trigger the UE to transmit SRS at the end of a timeslot at any desired power level. However, given that channel variation may be fast, signaling overhead for triggering multiple SRS transmissions by the UE could be considerable. Accordingly, a single trigger by the network node for the UE to transmit SRS at different transmit power levels may be preferred (e.g., at 10 dBm, 10 dBm, 13 dBm, 13 dBm, and so on). It is also noteworthy that cell-specific SRS resources required to facilitate closely-spaced SRS transmissions could render the NR slot usage less flexible. For instance, to allow SRS transmissions, consecutive slots may need to be dedicated to uplink (UL) transmissions or at least part of the consecutive slots may need to be dedicated to UL transmissions.

Thus, under the proposed scheme, a network node may use a single trigger to indicate, instruct or otherwise cause a UE to conduct a sequence of SRS transmissions at different transmit power levels (e.g., from one symbol to another). There may be a time gap between every two adjacent SRS transmissions so that SRS transmissions at different transmit power levels in closely-spaced time intervals do not create a challenge for the UE in terms of transmit waveform fidelity. For instance, SRS transmissions may take place at evenly-spaced OFDM symbols 1, 3, 5, and so on. The signaling overhead may be much reduced by configuring through radio resource control (RRC) signaling a magnitude of power ramp step and a number of SRS transmissions in a sequence. For instance, the network node may configure the UE such that UE transmits SRS at x, x+d, x+2d, . . . x+10d dBm in a sequence of SRS transmissions. For illustrative purposes and without limitation, in this example d=2 and x=0 dBm. Alternatively, x may also be determined jointly in dynamic signaling for SRS triggering along with semi-statically configured parameters.

Under a proposed scheme in accordance with the present disclosure, a UE may perform self-calibration in an event that the UE is equipped with a calibration circuit to observe relative phase difference between every two SRS transmissions at different transmit power levels. Under the proposed scheme, once the UE receives a transmitted precoding matrix index (TPMI) from the network node for PUSCH, the UE may assume that the TPMI is derived by the network node with a previous SRS transmission from the UE (but not the most recently transmitted SRS). For instance, the UE may transmit SRS at slots n−11 and n−1, and a TPMI may be signaled by the network node to be used for PUSCH at slot n. Then, the UE may assume that the TPMI is derived from the SRS transmitted at slot n−11, as the network node may not have sufficient time to process the SRS transmitted at slot n−1.

Under a proposed scheme in accordance with the present disclosure, for dynamic time-division duplexing (TDD), SRS received signal strength indicator (SRS-RSSI) and SRS reference signal received power (SRS-RSRP) may be used for cross-link interference (CLI) measurement. It may be beneficial that SRS transmission from an aggressor UE reflects faithfully the interference it generates when conducting PUSCH transmissions. Depending on whether the UE performs codebook-based transmission, non-codebook-based transmission or diversity transmission, behavior of the SRS transmission may not be the same. There may be several approaches to determining how SRS for CLI should be transmitted by the aggressor UE, including, for example and without limitation, autonomous determination and network node signaling.

Under the autonomous determination approach, a number of transmission port and any transmission precoder may be autonomously determined by the UE. The power of SRS transmission may also be aligned with PUSCH. For instance, the power of SRS transmission may be aligned with the most recent PUSCH or the most frequently used PUSCH. In any case, a rule may be utilized such that the network node can have knowledge about SRS transmission parameters (e.g., transmit power levels and time interval) not explicitly indicated by the aggressor UE.

Under the network node signaling approach, with codebook-based transmission, the network node may signal SRS Resource Indicator (SRI), TPMI and rank indicator (RI) (SRI+TPMI+RI) to the UE for SRS transmission. Moreover, under the network node signaling approach, with non-codebook-based transmission, the network node may signal SRIs to the UE. The signaling may be provided semi-statically or dynamically for the aggressor UE. The SRS transmission power may be aligned with PUSCH. For dynamic TDD, to reduce UE reception complexity in SRS-RSRP measurements, it may be necessary to constrain the number of SRS root indices of the aggressor UE in an adjacent cell to a small number (e.g., 1), which may be different from that in an SRS configuration suitable for other purposes (e.g., downlink/uplink channel state information (CSI) acquisition, beam management and the like). SRS configuration for dynamic TDD may be configured separately from other purposes.

Under the network node signaling approach, as the SRS transmission parameters may be aligned with PUSCHs, it may be feasible to include an SRS for CLI trigger in an UL downlink control information (DCI). The triggered SRS transmission may assume all the transmission parameters (e.g., in terms of SRI(s), TPMI and so on) for the co-triggered PUSCH. Moreover, a separate DCI may be considered. That is, SRS for CLI may be used to reflect long-term and averaged CLI, which may not be exactly aligned with the current need for PUSCH. It may be beneficial to decouple PUSCH transmission and SRS for CLI design. A separate DCI for SRS for CLI may also have the benefits for allowing a clean definition of NR features.

Under a proposed scheme in accordance with the present disclosure, it may be beneficial to define time-domain behavior for UEs from different cells. Specifically, UEs from the same cell may be configured to receive and transmit SRS at the same time. To facilitate efficient SRS transmission and reception at cell boundary (e.g., among three neighboring cells), some coordination pattern such as a mutually-hearable pattern may need to be defined. Accordingly, non-contiguous SRS transmission and reception may be necessary.

FIG. 2 illustrates an example scenario 200 in accordance with implementations of the present disclosure. In scenario 200, a mutually-hearable pattern for a number of cells (e.g., six cells as shown in FIG. 2) may be utilized for transmission and receiving. As shown in FIG. 2, according to the mutually-hearable pattern, for every two adjacent cells there is at least one timeslot in which both the adjacent cells are either transmitting or receiving. Similarly, according to the mutually-hearable pattern, for every two adjacent cells there is at least one timeslot in which one of the two adjacent cells is transmitting while the other of the two adjacent cells is receiving. Scenario 200 may be implemented by UE 110 and network node 120 of FIG. 1.

Considering the needs from the perspectives of RPD calibration and dynamic TDD, a separate DCI may be used to trigger aperiodic transmissions of SRS by a UE. The SRS transmission parameters may include, for example and without limitation, precoding information, indication for transmission power (e.g., staying the same for all transmissions or using a power ramp), and transmission timing (e.g., evenly spaced or non-evenly spaced). The SRS transmission parameters may be determined from semi-static signaling and/or dynamic signaling.

Illustrative Implementations

FIG. 3 illustrates an example wireless communication environment 300 in accordance with an implementation of the present disclosure. Wireless communication environment 300 may involve a communication apparatus 310 and a network apparatus 320 in wireless communication with each other. Each of communication apparatus 310 and network apparatus 320 may perform various functions to implement schemes, techniques, processes and methods described herein pertaining to utilization of SRS for RPD calibration in wireless communications, including scenarios 100 and 200 described above as well as processes 400 and 500 described below. Thus, communication apparatus 310 may be an example implementation of UE 110 in scenario 100, and network apparatus 320 may be an example implementation of network node 120 in scenario 100.

Communication apparatus 310 may be a part of an electronic apparatus, which may be a UE such as a portable or mobile apparatus, a wearable apparatus, a wireless communication apparatus or a computing apparatus. For instance, communication apparatus 310 may be implemented in a smartphone, a smartwatch, a personal digital assistant, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Moreover, communication apparatus 310 may also be a part of a machine type apparatus, which may be an IoT or NB-IoT apparatus such as an immobile or a stationary apparatus, a home apparatus, a wire communication apparatus or a computing apparatus. For instance, communication apparatus 310 may be implemented in a smart thermostat, a smart fridge, a smart door lock, a wireless speaker or a home control center. Alternatively, communication apparatus 310 may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, one or more reduced-instruction-set-computing (RISC) processors or one or more complex-instruction-set-computing (CISC) processors.

Communication apparatus 310 may include at least some of those components shown in FIG. 3 such as a processor 312, for example. Communication apparatus 310 may further include one or more other components not pertinent to the proposed scheme of the present disclosure (e.g., internal power supply, display device and/or user interface device), and, thus, such component(s) of communication apparatus 310 are neither shown in FIG. 3 nor described below in the interest of simplicity and brevity.

Network apparatus 320 may be a part of an electronic apparatus, which may be a network node such as a TRP, a base station, a small cell, a router or a gateway. For instance, network apparatus 320 may be implemented in an eNodeB in an LTE, LTE-Advanced or LTE-Advanced Pro network or in a gNB in a 5G, NR, IoT or NB-IoT network. Alternatively, network apparatus 320 may be implemented in the form of one or more IC chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, one or more RISC processors, or one or more CISC processors.

Network apparatus 320 may include at least some of those components shown in FIG. 3 such as a processor 322, for example. Network apparatus 320 may further include one or more other components not pertinent to the proposed scheme of the present disclosure (e.g., internal power supply, display device and/or user interface device), and, thus, such component(s) of network apparatus 320 are neither shown in FIG. 3 nor described below in the interest of simplicity and brevity.

In one aspect, each of processor 312 and processor 322 may be implemented in the form of one or more single-core processors, one or more multi-core processors, one or more RISC processors, or one or more CISC processors. That is, even though a singular term “a processor” is used herein to refer to processor 312 and processor 322, each of processor 312 and processor 322 may include multiple processors in some implementations and a single processor in other implementations in accordance with the present disclosure. In another aspect, each of processor 312 and processor 322 may be implemented in the form of hardware (and, optionally, firmware) with electronic components including, for example and without limitation, one or more transistors, one or more diodes, one or more capacitors, one or more resistors, one or more inductors, one or more memristors and/or one or more varactors that are configured and arranged to achieve specific purposes in accordance with the present disclosure. In other words, in at least some implementations, each of processor 312 and processor 322 is a special-purpose machine specifically designed, arranged and configured to perform specific tasks pertaining to utilization of SRS for RPD calibration in wireless communications in accordance with various implementations of the present disclosure.

In some implementations, communication apparatus 310 may also include a transceiver 316 coupled to processor 312 and capable of wirelessly transmitting and receiving data, signals and information. In some implementations, communication apparatus 310 may further include a memory 314 coupled to processor 312 and capable of being accessed by processor 312 and storing data therein. In some implementations, network apparatus 320 may also include a transceiver 326 coupled to processor 322 and capable of wirelessly transmitting and receiving data, signals and information. In some implementations, network apparatus 320 may further include a memory 324 coupled to processor 322 and capable of being accessed by processor 322 and storing data therein. Accordingly, communication apparatus 310 and network apparatus 320 may wirelessly communicate with each other via transceiver 316 and transceiver 326, respectively.

To aid better understanding, the following description of the operations, functionalities and capabilities of each of communication apparatus 310 and network apparatus 320 is provided in the context of a mobile communication environment in which communication apparatus 310 is implemented in or as a communication apparatus or a UE and network apparatus 320 is implemented in or as a network node (e.g., gNB or TRP) of a wireless network (e.g., 5G/NR mobile network).

In one aspect, processor 312 of communication apparatus 310 may receive, via transceiver 316, a single trigger signal from network apparatus 320. Moreover, processor 312 may transmit, via transceiver 316, a plurality of reference signals at different power levels in sequence to network apparatus 320 responsive to receiving the single trigger signal.

In some implementations, in transmitting the plurality of reference signals in sequence, processor 312 may perform a plurality of SRS transmissions in sequence.

In some implementations, in transmitting the plurality of reference signals at the different power levels, processor 312 may transmit the plurality of reference signals at a plurality of different power levels. In some implementations, at least two of the different power levels are at a same level (e.g., 10 dBm, 10 dBm, 13 dBm, 13 dBm, and so on).

In some implementations, in transmitting the plurality of reference signals at the different power levels, processor 312 may transmit the plurality of reference signals at the different power levels according to a predefined power ramp schedule.

In some implementations, in transmitting the plurality of reference signals at the different power levels, processor 312 may transmit the plurality of reference signals at a predefined power level.

In some implementations, in transmitting the plurality of reference signals in sequence, processor 312 may transmit the plurality of reference signals at evenly-spaced time intervals. Alternatively, in transmitting the plurality of reference signals in sequence, processor 312 may transmit the plurality of reference signals at non-evenly-spaced time intervals.

In some implementations, in transmitting the plurality of reference signals, processor 312 may transmit the plurality of reference signals as evenly-spaced OFDM symbols in a time domain.

In some implementations, processor 312 may also receive, via transceiver 316, signaling from network apparatus 320. Additionally, processor 312 may configure, based on the signaling, one or more parameters with respect to transmission of the plurality of reference signals in sequence.

In some implementations, the signaling may include radio resource control (RRC) signaling.

In some implementations, the one or more parameters may include at least one of: (1) a magnitude of a power ramp step for varying a transmission power in transmitting the plurality of reference signals; (2) a number of reference signals to be transmitted in sequence; and (3) a transmit timing for each reference signal of the plurality of reference signals.

In some implementations, the one or more parameters may include at least one of precoding information, one or more levels of transmission power, and transmission timing.

Additionally, or alternatively, processor 312 may configure, based on the signaling, a mutually-hearable pattern in a time domain with respect to one or more neighboring cells of the wireless network. In some implementations, in transmitting the plurality of reference signals in sequence, processor 312 may transmit the plurality of reference signals in sequence using the mutually-hearable pattern.

Additionally, processor 312 may receive, via transceiver 316, signaling from network apparatus 320. Then, processor 312 may combine the one or more parameters with information conveyed in the trigger signal to derive precoding information, one or more levels of transmission power, and transmission timing.

In one aspect, processor 322 of network apparatus 310 may transmit, via transceiver 326, a single trigger signal to communication apparatus 310. Additionally, processor 322 may receive, via transceiver 316, a plurality of reference signals in sequence from communication apparatus 310 responsive to transmitting the single trigger signal. Moreover, processor 322 may perform RPD calibration based on the plurality of reference signals.

In some implementations, processor 332 may transmit, via transceiver 326, signaling (e.g., RRC signaling) to communication apparatus 310. The signaling may configure one or more parameters on communication apparatus 310 with respect to transmission of the plurality of reference signals in sequence. Additionally, or alternatively, the signaling may configure a mutually-hearable pattern in a time domain with respect to one or more neighboring cells of the wireless network. In such cases, communication apparatus 310 may transmit the plurality of reference signals in sequence using the mutually-hearable pattern.

Illustrative Processes

FIG. 4 illustrates an example process 400 in accordance with an implementation of the present disclosure. Process 400 may be an example implementation of scenario 100 and scenario 200, or a combination thereof, whether partially or completely, with respect to utilization of SRS for RPD calibration in wireless communications in accordance with the present disclosure. Process 400 may represent an aspect of implementation of features of communication apparatus 310. Process 400 may include one or more operations, actions, or functions as illustrated by one or more of blocks 410 and 420. Although illustrated as discrete blocks, various blocks of process 400 may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks of process 400 may executed in the order shown in FIG. 4 or, alternatively, in a different order, and one or more of the blocks of process 400 may be repeated one or more times. Process 400 may be implemented by communication apparatus 310 or any suitable UE or machine type devices. Solely for illustrative purposes and without limitation, process 400 is described below in the context of communication apparatus 310 as a UE and network apparatus 320 as a network node of a wireless network. Process 400 may begin at block 410.

At 410, process 400 may involve processor 312 of communication apparatus 310 receiving, via transceiver 316, a single trigger signal from network apparatus 320. Process 400 may proceed from 410 to 420.

At 420, process 400 may involve processor 312 transmitting, via transceiver 316, a plurality of reference signals in sequence to network apparatus 320 responsive to receiving the single trigger signal.

In some implementations, in transmitting the plurality of reference signals in sequence, process 400 may involve processor 312 performing a plurality of SRS transmissions, the transmit power levels of which can be different, in sequence.

In some implementations, in transmitting the plurality of reference signals at the different power levels, process 400 may involve processor 312 transmitting the plurality of reference signals at different transmit power levels. In some implementations, at least two of the different power levels are at a same level (e.g., at 10 dBm, 10 dBm, 13 dBm, 13 dBm, and so on).

In some implementations, in transmitting the plurality of reference signals at the different power levels, process 400 may involve processor 312 transmitting the plurality of reference signals at the different power levels according to a predefined power ramp schedule.

In some implementations, in transmitting the plurality of reference signals at the different power levels, process 400 may involve processor 312 transmitting the plurality of reference signals at a predefined power level.

In some implementations, in transmitting the plurality of reference signals in sequence, process 400 may involve processor 312 transmitting the plurality of reference signals at evenly-spaced time intervals. Alternatively, in transmitting the plurality of reference signals in sequence, process 400 may involve processor 312 transmitting the plurality of reference signals at non-evenly-spaced time intervals.

In some implementations, in transmitting the plurality of reference signals, process 400 may involve processor 312 transmitting the plurality of reference signals as evenly-spaced OFDM symbols in a time domain.

In some implementations, process 400 may further involve processor 312 performing other operations. For instance, process 400 may involve processor 312 receiving, via transceiver 316, signaling from network apparatus 320. Additionally, process 400 may involve processor 312 configuring, based on the signaling, one or more parameters with respect to transmission of the plurality of reference signals in sequence.

In some implementations, the signaling may include radio resource control (RRC) signaling.

In some implementations, the one or more parameters may include at least one of: (1) a magnitude of a power ramp step for varying a transmission power in transmitting the plurality of reference signals; (2) a number of reference signals to be transmitted in sequence; and (3) a transmit timing for each reference signal of the plurality of reference signals.

In some implementations, the one or more parameters may include at least one of precoding information, one or more levels of transmission power, and transmission timing(s).

In some implementations, process 400 may further involve processor 312 performing other operations. For instance, process 400 may involve processor 312 receiving, via transceiver 316, signaling from network apparatus 320. Additionally, process 400 may involve processor 312 configuring, based on the signaling, a mutually-hearable pattern in a time domain with respect to one or more neighboring cells of the wireless network. In some implementations, in transmitting the plurality of reference signals in sequence, process 400 may involve processor 312 transmitting the plurality of reference signals in sequence using the mutually-hearable pattern.

In some implementations, process 400 may further involve processor 312 performing other operations. For instance, process 400 may involve processor 312 receiving, via transceiver 316, signaling from network apparatus 320. Moreover, process 400 may involve processor 312 combining the one or more parameters with information conveyed in the trigger signal to derive precoding information, one or more levels of transmission power, and transmission timing.

FIG. 5 illustrates an example process 500 in accordance with an implementation of the present disclosure. Process 500 may be an example implementation of scenario 100 and scenario 200, or a combination thereof, whether partially or completely, with respect to utilization of SRS for RPD calibration in wireless communications in accordance with the present disclosure. Process 500 may represent an aspect of implementation of features of communication apparatus 310. Process 500 may include one or more operations, actions, or functions as illustrated by one or more of blocks 510, 520 and 520. Although illustrated as discrete blocks, various blocks of process 500 may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks of process 500 may executed in the order shown in FIG. 5 or, alternatively, in a different order, and one or more of the blocks of process 500 may be repeated one or more times. Process 500 may be implemented by communication apparatus 310 or any suitable UE or machine type devices. Solely for illustrative purposes and without limitation, process 500 is described below in the context of communication apparatus 310 as a UE and network apparatus 320 as a network node of a wireless network. Process 500 may begin at block 510.

At 510, process 500 may involve processor 322 of network apparatus 310 transmitting, via transceiver 326, a single trigger signal to communication apparatus 310. Process 500 may proceed from 510 to 520.

At 520, process 500 may involve processor 322 receiving, via transceiver 316, a plurality of reference signals in sequence from communication apparatus 310 responsive to transmitting the single trigger signal. Process 500 may proceed from 520 to 530.

At 530, process 500 may involve processor 322 performing RPD calibration based on the plurality of reference signals.

In some implementations, in receiving the plurality of reference signals in sequence, process 500 may involve processor 322 receiving a plurality of SRS transmissions in sequence.

In some implementations, in receiving the plurality of reference signals, process 500 may involve processor 322 receiving the plurality of reference signals which may come at different power levels.

In some implementations, in receiving the plurality of reference signals, process 500 may involve processor 322 receiving the plurality of reference signals at different power levels according to a predefined power ramp schedule.

In some implementations, in receiving the plurality of reference signals, process 500 may involve processor 322 receiving the plurality of reference signals at a predefined power level(s).

In some implementations, in receiving the plurality of reference signals in sequence, process 500 may involve processor 322 receiving the plurality of reference signals at evenly-spaced time intervals.

In some implementations, in receiving the plurality of reference signals in sequence, process 500 may involve processor 322 receiving the plurality of reference signals as evenly-spaced OFDM symbols in a time domain.

In some implementations, process 500 may further involve processor 332 transmitting, via transceiver 326, signaling to communication apparatus 310. The signaling may configure one or more parameters on communication apparatus 310 with respect to transmission of the plurality of reference signals in sequence.

In some implementations, the signaling may include RRC signaling.

In some implementations, the one or more parameters may include at least one of: (1) a magnitude of a power ramp step for varying a transmission power in transmitting the plurality of reference signals; (2) a number of reference signals to be transmitted in sequence; and (3) a time interval between every two adjacent reference signals to be transmitted in sequence.

In some implementations, the one or more parameters may include at least one of precoding information, one or more levels of transmission power, and transmission timing.

In some implementations, process 500 may further involve processor 332 transmitting, via transceiver 326, signaling to communication apparatus 310. The signaling may configure a mutually-hearable pattern in a time domain with respect to one or more neighboring cells of the wireless network. Moreover, communication apparatus 310 may transmit the plurality of reference signals in sequence using the mutually-hearable pattern.

The method of claim 8, wherein the one or more parameters comprise at least one of precoding information, one or more levels of transmission power, and transmission timing.

11 a. The method of claim 8, wherein the one or more parameters is combined with the information conveyed in the trigger signal to derive precoding information, one or more levels of transmission power and transmission timing.

ADDITIONAL NOTES

The herein-described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected”, or “operably coupled”, to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable”, to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.

Further, with respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

Moreover, it will be understood by those skilled in the art that, in general, terms used herein, and especially in the appended claims, e.g., bodies of the appended claims, are generally intended as “open” terms, e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc. It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to implementations containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an,” e.g., “a” and/or “an” should be interpreted to mean “at least one” or “one or more;” the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number, e.g., the bare recitation of “two recitations,” without other modifiers, means at least two recitations, or two or more recitations. Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention, e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc. In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention, e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc. It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

From the foregoing, it will be appreciated that various implementations of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various implementations disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims. 

What is claimed is:
 1. A method, comprising: receiving, by a processor of a user equipment (UE), a single trigger signal from a network node of a wireless network; and transmitting, by the processor, a plurality of reference signals at different power levels in sequence to the network node responsive to receiving the single trigger signal.
 2. The method of claim 1, wherein the transmitting of the plurality of reference signals in sequence comprises performing a plurality of sounding reference signal (SRS) transmissions in sequence.
 3. The method of claim 1, wherein the transmitting of the plurality of reference signals at the different power levels comprises transmitting the plurality of reference signals at a plurality of different power levels, wherein at least two of the different power levels are at a same level.
 4. The method of claim 1, wherein the transmitting of the plurality of reference signals at the different power levels comprises transmitting the plurality of reference signals at the different power levels according to a predefined power ramp schedule.
 5. The method of claim 1, wherein the transmitting of the plurality of reference signals at the different power levels comprises transmitting the plurality of reference signals at predefined power levels.
 6. The method of claim 1, wherein the transmitting of the plurality of reference signals in sequence comprises transmitting the plurality of reference signals at evenly-spaced time intervals.
 7. The method of claim 1, wherein the transmitting of the plurality of reference signals in sequence comprises transmitting the plurality of reference signals at non-evenly-spaced time intervals.
 8. The method of claim 1, wherein the transmitting of the plurality of reference signals in sequence comprises transmitting the plurality of reference signals as evenly-spaced orthogonal frequency-division multiplexing (OFDM) symbols in a time domain.
 9. The method of claim 1, further comprising: receiving, by the processor, signaling from the network node; and configuring, by the processor based on the signaling, one or more parameters with respect to transmission of the plurality of reference signals in sequence, wherein the signaling comprises radio resource control (RRC) signaling.
 10. The method of claim 8, wherein the one or more parameters comprise at least one of: a magnitude of a power ramp step for varying a transmission power in transmitting the plurality of reference signals; a number of reference signals to be transmitted in sequence; and a transmit timing for each reference signal of the plurality of reference signals.
 11. The method of claim 1, further comprising: receiving, by the processor, signaling from the network node; and combining the one or more parameters with information conveyed in the trigger signal to derive precoding information, one or more levels of transmission power, and transmission timing.
 12. The method of claim 1, further comprising: receiving, by the processor, signaling from the network node; and configuring, by the processor based on the signaling, a mutually-hearable pattern in a time domain with respect to one or more neighboring cells of the wireless network, wherein the transmitting of the plurality of reference signals in sequence comprises transmitting the plurality of reference signals in sequence using the mutually-hearable pattern.
 13. An apparatus, comprising: a transceiver capable of wirelessly communicating with a network node of a wireless network; and a processor coupled to the transceiver, the processor capable of: receiving, via the transceiver, signaling from the network node; configuring, based on the signaling, one or more parameters with respect to transmission of a plurality of reference signals in sequence; receiving, via the transceiver, a single trigger signal from the network node; and transmitting, via the transceiver, the plurality of reference signals in sequence to the network node responsive to receiving the single trigger signal.
 14. The apparatus of claim 13, wherein, in transmitting the plurality of reference signals in sequence, the processor is capable of performing a plurality of sounding reference signal (SRS) transmissions in sequence.
 15. The apparatus of claim 13, wherein, in transmitting the plurality of reference signals, the processor is capable of transmitting the plurality of reference signals at different power levels according to a predefined power ramp schedule and at evenly-spaced time intervals.
 16. The apparatus of claim 13, wherein, in transmitting the plurality of reference signals, the processor is capable of transmitting the plurality of reference signals at a predefined power level and at evenly-spaced time intervals.
 17. The apparatus of claim 13, wherein, in transmitting the plurality of reference signals in sequence, the processor is capable of transmitting the plurality of reference signals as evenly-spaced orthogonal frequency-division multiplexing (OFDM) symbols in a time domain.
 18. The apparatus of claim 13, wherein the signaling comprises radio resource control (RRC) signaling.
 19. The apparatus of claim 13, wherein the one or more parameters comprise at least one of: a magnitude of a power ramp step for varying a transmission power in transmitting the plurality of reference signals; a number of reference signals to be transmitted in sequence; and a time interval between every two adjacent reference signals to be transmitted in sequence.
 20. The apparatus of claim 13, wherein the processor is further capable of: configuring, based on the signaling, a mutually-hearable pattern in a time domain with respect to one or more neighboring cells of the wireless network, wherein the transmitting of the plurality of reference signals in sequence comprises transmitting the plurality of reference signals in sequence using the mutually-hearable pattern. 